In the wake of sexual harassment allegations against a now former Amazon executive, a group that advocates for investors sent a letter last week to the online giant, urging it to improve the diversity of its senior executive ranks, among other things.

The letter is the second filed by CtW Investment Group, which works with union-sponsored pension funds, and a sign that some investors are growing concerned about the reputation hit companies could face from the recent flood of harassment headlines.

“We believe that the evidence suggests that Amazon’s gender diversity gap creates significant risks for long-term shareholders, and that further delays in rethinking Amazon’s approach to human capital management may have dire consequences,” the organization’s executive director, Dieter Waizenegger, said in the letter, which is addressed to Amazon chairman and chief executive Jeffrey P. Bezos. (Bezos owns The Washington Post.)

The letter also cites the perception of Amazon as “an excessively high-pressure workplace” and calls for the board to take a number of steps, from setting targets for gender diversity to having a labor-law expert review employment contracts. CtW, which says the pension funds it works with hold about 1 million Amazon shares, or 0.2 percent, also plans to submit a shareholder resolution. It is not clear whether the proposal would become part of Amazon’s next proxy statement, which is required of a firm when soliciting shareholder votes. Companies can request that the U.S. Securities and Exchange Commission let them exclude proposals if they pertain to “ordinary business operations.”

Richard Clayton, CtW’s research director, said that one of the company’s concerns with Amazon was the time lag between 2015, when producer Isa Hackett said she made complaints to the company about behavior by former executive Roy Price, and this October, when Price resigned from Amazon after being suspended by the company. “Why was there was a two-year delay?” Clayton asked. “We’d want to hear the board explain why that happened.” (An email to a lawyer who is reported to represent Price was not immediately returned.)

The letter also cites the number of women Amazon has in senior executive roles compared with other tech companies, and says that could have an impact on how the company addresses allegations. It cited numbers from a recent New York Times story, which reported that just one of the top 16 executives (6 percent) at Amazon, known as the “S-team,” is a woman. At Apple, five of the top 19 executives listed on its website (26 percent) are women. Six of the 13 people (46 percent) on Google chief executive Sundar Pichai’s team are women, and three of the 16 executives listed on Microsoft’s website (19 percent) are female.

An Amazon spokesman declined to comment on the letter. In a statement previously reported by the Hollywood Reporter, where Hackett described her allegations, an Amazon spokesperson said “we take seriously any questions about the conduct of our employees,” and “we expect people to set high standards for themselves; we encourage people to raise any concerns and we make it a priority to investigate and address them.”

Women run several of Amazon’s businesses or divisions, including Stephenie Landry at Prime Now, Jennifer Cast at Amazon Books and Elaine Chang, Amazon’s leader in China. But these women are not part of the S-team, which has been described as the core group of senior executives that leads the company. In the company’s public diversity report, Amazon says 25 percent of managers are women on a global level.

CtW’s letter to Amazon is the second it has sent as sexual harassment headlines have piled up against powerful figures in media and business, and Clayton said it is “actively considering” sending letters to other companies, though nothing is definitive yet. Following the sexual harassment scandal at Fox News, CtW sent an October letter to 21st Century Fox, charging that the board failed to “effectively address the longtime ethics crisis” and pressing it to refresh its lineup of directors.

So far, investors have not been pushing many proxy resolutions focused on corporate harassment policies, and it’s not expected to be a big factor during next year’s annual meeting season, according to the research arm of proxy adviser Institutional Shareholder Services. But that doesn’t mean investors aren’t concerned about issues related to gender. Proposals on gender diversity on the board, more broadly, have been growing in recent years, from just seven in 2012 to 37 this year.

Meanwhile, Eve Ellis, a financial adviser at Morgan Stanley who co-manages a portfolio that examines board diversity when selecting investments, said in an email that investors she talks with “are becoming increasingly aware of the negative impact sexual harassment charges can have on a firm’s performance,” and she watches for signs her investments are with companies that have policies in place.